serving webapps out of arbitrary subfolders with nginx

I'm serving webapps out of arbitrary subfolders on a domain. i.e.

example.com/app-one (with example.com/app-one/page served by app-one)
example.com/folder/app-two (with example.com/folder/app-two/page served by app-two)

I have a nginx config that works just fine for the root level, but I'm a little stumped on how to handle subfolders. I could make location /app-one blocks, of course, but we have dozens of these and we'd like to avoid having to expliticly specify each one.

Is there any way to get try_files to essentially recurse up the folder structure until it hits an index.php file?

server {
    server_name example.com

    location / {
        root /srv/web/example.com;
        index index.php index.html;
        try_files $uri $uri/ /index.php?q=$q&$args;
    }

    # pass *.php files to the PHP tier
    location ~ \.php$ {
        root /srv/web/example.com;
        include /etc/nginx/fastcgi_params;
        fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
        fastcgi_pass php:9000;
    }
}